Spacetravel is going to be a race again, since upcoming economies as China, announce their plans to head for manned missions and possible moon missions, and also other nations are upcoming as spacetraveling countries (like India).
The american plans head for the moon again, set up permanent bases on the moon, and maybe in the long time we might have a manned mission to mars.
Apart from all the unmanned far solar missions, seems we are heading for some more exciting times at this front, where new frontiers are met.
But, for the point of discussing this, the purpose of this post is to derive to the question of what is the purpose of space travel. There are a number of goals to be met, like scientific exploration and the expansion of knowledge, etc.
There is in itself nothing wrong with investing money into sciencific exploration, without reaons of budget and other needs.
There are also economic goals of course. Part of the spacefaring activity serves for economic goals, like communication, GPS, weather forecast, etc.
However these direct economic goals are restricted to earth orbit satelites only.
Recently though, in the perspective of upcoming space travel events, a number of reasons have been lay out for grounding space travel at the basis of economic goals.
Like for instance there are the statements that on the moon and other celestial bodies, we may find new resources, which are valuable. That might be true, but to what extend can we harvest such resources at acceptable price levels? Shipping goods to earth is very expensive, for example, even if there are unlimited quantities to find. So only resources for self sustainance come into the picture, but will that ever be self sufficient?
What we have today is just some 100 kg of extraterrestial rocks. Consider the prices of that rock in terms of the money invested to get them. It turns out, those rock are priced astronomically (just try to calculate that!). As technology advances, the price will sink of course (and in the first place, we didn't harvest these rocks and other materials for economic purposes, but purely for scientific goals), but to what extend? Can resources of space ever compete with earth resources?
What resources do we need what we can not get on earth?
Can a space colony be ever self sustained, even survive without any investments or goods from earth? Is that a goal we must work on, to increase our chance of surviving?
I think in all these aspects, colonization is different from the colonizations of our own world, since we have a livable habitat on earth, and don't have to invest enormous amounts to create a colony that can survive on it's own.
And also recently, Stephen Hawking mixed himself in the discussion, pointing out that space travel is needed in the effort to save humanity. In that statement he mainly mentioned the danger of biologic or other warfare, not even a word about environemental problems and resource depletion and the problems of peak oil or things like that, which seem to me a bigger problem, affecting more people and bigger economic problems, then some isolated acts of terror.
The 'war on terror' is IMHO some fake artefact of an imperialist society, which can only keep it present status as ruler of the world, at the basis of the exploitation of others and to deny others the rights to use our common natural resources; every resistance to current 'world order' is ranked as 'terror', in order not to change the current dominating status of the imperialist countries, even though this denies then in principle other nations and people to have a standard of living comparable to ours.
Regarding these aformentioned grounds for space travel:
I have tried to figure out wether such reasons are grounded. What problems of humanity can in fact be solved by space travel? Problems, for instance related to resource depletion, danger of major catastrophies (natural or otherwise) that might wipe out humanity, the environemental issues, etc.
My reasoning started out from the fact that - apart from the economic effects of some part of it,the commercial satelites and the economic services they provide - space travel as such is just costing huge economic resources.
Further I reason that no matter how our technology might evolve, the establishing of colonies in space, which can be self supporting (produce on average enoough economic value to enable their support), seems to me only a dream if at all likely.
Without costy space travel connections for supplies and goods, those colonies can never be self supporting, and even if there are returns (valuable alloys or other resources), they won't come in such quantities that it can pay off. Although of course the price mechanism will predict that such resources would be very costy.
And even it that DOES become plausible after many decades or centuries, we have to realise that such colonies have to become very large to be productive at all, and all that time and during that time, they will cost valuable resources on earth.
Currently the earth population doubles every 25 years or so. Resources, and esp. energy resources are already becoming depleted (gas and oil reserves for sure will not be sufficient for decades, and if we don't have the technology to supply enough energy, we will head for a major catastrophy) and we can already see the end of the oil area.
Growing economies of former third world countries, which demand their share of the global resources, will enlarge the upcoming problems.
In the perspective of that, how grounded is the appeal and call for space travel, under the claim that it can solve earths problems.
I mean, even if we could build a colony on mars and inhabit it with the same number of people as earth currently has, this would only help for 25 years, as long as the rate of population growth is at this level.
The growth level is reducing within 50 years or so, and perhaps stabilizing, but the earth will be dominately be populated with rather poor people, which will also want their (justifiable) share of consumer goods and earth resources.
Are we going into space, just to evade the major consequences of this?
In some or other way, I think the call for going into space, to help forward and maintain human existence, sounds somewhat like the captain's call on a sinking ship to abandon ship.
And if the reason to go into space are such, and not well grounded, we might want to re-evaluate the resources we spend on them, and think for more realistic measures to be taken to realy help forward the progress and well being of all of mankind.
If we can think we can inhabit the moon and mars on the basis of space technology, how much less effort would it be to make earth's dessert inhabitable again for the well being of people on earth??
Please note that desserts can in the near future be profitable when we harvest large scale sun energy there, and also can transform salt water into drinkable water, which would for many reasons help forward humanity much more as creating those habitats on the moon or mars, at much lesser costs and much more return on investment. Wouldn't it be much more wise to first try to make those wastland into farmland and apply large scale solar technology to also reduce the real problems of climate change, environment pollution, and depletion of oil, not to mention the problems related to peak oil?
I don't make an argument against space travel as such, or against human space travel, not even against trying to concur the universe and create livable and possible self sustaining habitats outside of earth.
But for the near future I would think, when balancing the investments against the time it will pay-off and the amount of expected return, the global economy would benefit more if for example the australian desserts, the sahara and the gobi deserts would become inhabitable by means of harvesting huge scale solar energy and irrigations for producing energy and agricultural goods desperaly needed for people on earth. The same investment in space can never return that much that quick and have such good benefits for people on earth, so why not first make these investments and solve some real problems before we head into space?
Not that I am against any human space mission as such, but in this moment of time, there are no other real grounds for doing it then scientific endavour and increasing knowledge, which is good I think, but the scenario of helping to avoid or solve some real problems, seems to be based on fiction, at least for the near future. We may think of that on the long term, but we must also and with even more effort think for the near future of humanity (all of humanity, not just the wealthy /rich people, earth is dominated with people who don't have a reasonable standard of living), which is in desperate needs for more living space, energy resources, water (!) and farmland and such. We have that here, we don't have to go to mars or to the moon to turn unliveable dessert like areas onto liveable and productive habitats, with much less effort and much more benefit we can do such projects on earth.
If human space exploration is done under the terms of the desperatedness of not being able to solve the real problems on earth, and merely deals with the scenario that those problems are not going to be solved but end up in real chaos, war and other catastrophes, and our only chance would be to survive to get into space and start again somewhere else (with the disadvantage of not having a biosphere that was active for billions of years!) I think that such grounds are totaly false and dillusive. They are the thoughts of mad man, who can not help himself and is desperate and thinks in 'solutions' that even worsen the problems (space exploration costs huge resources desperately needed somewhere else!), instead of solving them!